mu SR studies of Pu metal and the Pu-based superconductor PuCoGa5

作者：Heffner Robert H^*; Bauer Eric D; Chung B; Fluss Michael J; Higemoto Wataru; Ito Takashi U; MacLaughlin Douglas E; Morales Luis A; Morris Gerald D; Ohishi Kazuki; Sarrao John L; Shu Lei

来源：Journal of the Physical Society of Japan, 2006, 75: 14-19.

DOI：10.1143/JPSJS.75S.14

• mu SR
• plutonium
• superconductivity
• magnetism

We present recent measurements of the magnetic properties of Pu metal and the superconducting properties of PuCoGa5 using the mu SR technique. Our measurements set the most stringent upper limits to date on the magnitude of the ordered moments mu(ord) in alpha-Pu and delta-stabilized Pu (alloyed with 4.3 at. % Ga) in zero applied field: mu(ord) <= 10(-3) mu B at T congruent to 4 K. Measurements of the in-plane magnetic-field penetration depth lambda(T) in PuCoGa5 (T-c = 18.5 K) for 0.06 T applied field (approximate to 2 - 5 x H-c1) show that the temperature dependence of the superfluid density, and therefore Delta lambda(T) = lambda(T) - lambda(0), are proportional to T for T/T-c <= 0.5. We estimate that.(0) = 241(3) nm. We also find no evidence for a time-reversal-symmetry violating superconducting order parameter. Taken together the measurements in PuCoGa5 are, therefore, consistent with an even-parity (pseudo-spin singlet), d-wave pairing state.

• 出版日期2006-1-1
• 单位Los Alamos